Shock absorber



Nov. 28, 1933. R, F, POE 1,937,126

SHOCK ABSORBER Filed Feb. 19, 1931 2 Sheets-Sheet l 4 u, AW

R. F. POE

SHOCK ABSORBER Nov. 28, 1933.

Filed Feb. 19, 1931 2 Sheets-Sheet 2 Patented Nov. 28, 1933 v y p I d 1entree smrss TENT; ,orrics J I 1,937,126 7' I T j i sHo'oi- ;essences Va W Ralph; F. Pee, Eufialo, N. Y, assignor to Hal de v e EngineeringCorporation, Bnfialo, N..Y., acorporation of New York 1 p 1 ApplicationFebruary 1 9, 1931. Serial N0.' 516,9661

7 Claims. (01. 188 89 This invention relates to a shock absorber of withthe axis of the; bore of the peripheral 1 y the hydraulic type forabsorbing the shock bewall 10. i i 1 tween two relatively movablebodies, such for The body of the shock absorber is attached example asthe frame and axle of an automobile tonne of the relatively movablemembers be- 5 which move relatively to one another While the tween whichthe shock is to be absorbed,l,for'60v 1 car is passing over unevenplaces in the roadinstance the frame of an automobile ior which. way.purposethis body is" provided on its'opp'osite The object of thisinvention is to produce a sides with perforated lugsl8;wh'ich.areadapted shock absorber of this character which is simple-to receive bolts, screws or similar'ffastenings forand compact inconstruction, low in cost of proattaching, the body to said frame. Y I-66 duction, efiicient in operation and not liable to The space betweenthe cylindrical bore of'th'e 1 get out of order. wall 10 and theopposing inner fiat faces of the In the accompanying drawings:- rear andfront heads of the same is divided into Fig. 1 is a front elevation ofan approved two working chambers 19, 20by a parti tio'n havform of myinvention with the front cover or ing twodiametrically opposite sections21 and 70;

head of the body, the operating arm and asso- 22 arranged respectivelyabove and below 'the ciated parts omitted. v axis of the bodyiandengaging their'outer-ends Fig. 2 is a top plan view of the same with thewith thebore of the circular wall 10. Adjacent: cover of thereplenishing chamber omitted. to the rear wall- 11 the inner ends ofthe'parti- Figs. 3 and 4 are vertical longitudinal sections tions areconnected with each other by'rne'ans of 75.

taken on the correspondingly numbered lines in a centering ring23jwl'1ich' fits over the centering Fig. 1. g r pin 16 oft-he rear headassho'wn in Fig.3. R0

- Figs. 5 and 6 are fragmentary horizontal sectation of this partition"is prevent'ed'by two retions, on an enlarged scale,'tak.en on lines 5-5taining'pins 2 l ,feach of which is arrangedhori-i,

and 6--6, Fig. 1, respectively. zontally and lengthwise and engageswith} a cir- .89:

Fig. '7 a vertical transverse section taken on cular seat formed partlyin the bore of the wall line 7--7, Fig. 3. 10,;as shown'at 2 5 andpartly in'theouterend 8 is a front elevation of theshock abof therespective partition section; as shown at corber embody my inventionand. showing a 26 in Fig. Each of theretaining pins there- ---z 4 vmodified form of the same. vfore crosses a joint between the respectivepar- Fig. 9 is a vertical longitudinal section taken tition' section andthe peripheral wall of the on line 99, Fig. 8. body andnot only assistsin holding the parti- In the following description similar characterstion againstturningbut also serves to close this: of reference indicatelilie'parts in the several jointso asto preventleakage of liquid through3 figures of the drawings. T the same from oneside ofthisfpartition;tothe' The body, of thehydrauc shock absorber other. A I1 v shown Figs. 1-? com rises a peripheral wall The two,w'orleing"chambersjare adapted to 10, a rear head 11 which closes therear. end'of contain a resistance liquid which operates to the spacewithin said wall and is preferably absorb the shock to which therelatively movable 40 formed integral therewith, as shown in Figs. 3members aresnbjected and this 'liquid is disv and i, and a front wall 12which is preferably placed in, the working chambers from one endreinovably secured to the front end of the pethereof to ,t eother by twopistons 27,28 which ripheral wall and connectedtherewith by means engagetheir "outer ends with the hereof the of a screw joint 13 between theperiphery of peripheral wall while their inner. ends are con-'- 1' thehead 12 and th front part of the bore of nected with each otherby. ahub'29Qwhich enthe wall 16. At margin the front head 12 is gages itsopposite sides with the inner endsof provided with an annular flange 14which overthe partition sections 21 and 22. laps the front of the wall10, a leak-tight. The numeral 30 represents an operating shaft jointbeing produced between those parts by inwhich is journaled in thebearing l'lonthefront so terposing a packing 15 between the same. headand connected at its rear end with the hub The inner side of the rearhead 11 is provided 29 while its front. end is provided outside of theth a forwardly projecting centering pin 16 absorber body with anoperatingarm 31 which is the front head 12 is provided with a cenadaptedto be connected with the other member" tral bearing 17 which latter andthe centering which is movable relatively to the frame of the 55 pin 16are axially in line with each other and automobile such for example. asthe axle whichlip bone, as shown in Fig. '7, and a similar passagecarries the running wheels of the automobile and is connected with. theframe of the same by means of a spring system. On its front side thefront head of the body is provided with a neck 32 hav: ing a countersunkrecess on its front side which receives a packing for producing aleak-tight joint between the front part of the front head 12 and theoperating shaft,- which'pack'mgflin the present case consists of apacking ring 33 surrounding the shaft 3i) and bearing at its rear endagainst the bottom 34 of the recess in said neck and a retaining ringhaving an annular longitudinal flange 35 interposed between theperiphery of the packing ring 39 and the bore 36 of the plished in thepresent instance by a dial ietric'al v passage 38 formed mu piston huband connectingthe low pressure ends of the working cham- '39 arranged onthe inner end of the hub 29 and connecting the high pressureends of theworking chambers. V k i Means are, however, provided whereby the flow ofresistance liquid from the low. pressure end of one working chamber tothe high pressure end of the-otherworking chamber is permitted withcomparative freedom so as to area a comparatively low'shockabsorbing'action of the absorber but theflow of the resistance liquid inthe-opposite direction, that is to say from the high pressure end of oneworking chamber to the low pressure end of the other working chamber isw cut off and thereby confines the resistance liquid Qtoa greater extentin the high pressure end of oneof the working chambers as the pistontherein movesto the respective end of thes'ame and thereby increases theshock absorbing action ofitheinstruinent atthis time accordingly. Thisis preferably accomplished in the present ,fcase by a check valved portwhich includes a check valve chamber' 40 arranged in the upper partitionsection 21 and extendingfto the frontend thereof, aninlet 41 connectingthe rear end of this valve "chamber with the low pressure end 5 of theworking chamber 29 on one side of this partition, an outlet 42formed inthe front end of the-respective partition section and extending from thefront, end of the valve chamber 4;.0 to

- the adjacent 'high pressure end of the working chamber 19, a valveseat 43 formed in the valve chamber 40 and facing toward the highpressure end of the working chamber 19 and a ball valve ie arranged inthe valve chamber 40 and movable'toward and from the valve seat 4:3therein,

as shown in Figs. 1, 3, 6.

As the pistons effect a low pressure stroke, which is in a directionreverseto that indicated by'theiarrows'i'n Figs. 1 and 7 while the frameand 'ax'leof the car move one toward the other,

the'resistance liquid is permitted to pass with comparative freedom fromthe upper end or low compression end of the working chamber 20 throughthe check valved port in the partition 21 .topheupper'or highcompression end of the workingchamber 19 during which time the check thevalve .44 is opened and does not obstruct the flow of resistance liquidtherethrough.

When, however, the pistons effect a high pressure stroke in thedirection indicated by the arrows in land 7 which occurs when the frameand axle of the car move away from each other, then the check'valve 4eengages the seat 43 and thus confines the resistance liquidin the upperor high compression end of the working chamber 19 and causes the same tooffer a higher resistance to the upward movement of the piston 27 and t-ereby increase the shock absorbing effect of the instrumentaccordingly.

, Relief means are provided for automatically unloading part of theresistance liquid from the high pressure end of one of the workingchambers to the'lowpressure end of the other-working chamber forrendering riding of the carv more agreeable.

In instruments of this type, as heretofore ccnstructed, the spring loadrelief valveis made to release at low enough pressure to avoid vcomfortable ride over small obstructions, such. as cobblestones orbricks, at which time the movernc ts are rapid but short; but thecontrol, iding qualities over large'obstructions of the i which produceviolent, heavy bumps or depressions of longer duration isnot suflicient.

A relief. valve mechanism has therefore been provided in which a valvechamber acts as an in-l termediate pressure chamber and a spring closedvalve therein is lifted from its seat by the differenvaive chamber 45which'niay extend to the front end of this partition section, an inlet46 arrange at the rear of the. partition 22 and extending laterally fromthe rear end of the valve chamber l5 to the'high ber 29, an outlet 47extending from the interinediate'part of the valve chamber 45 to the lowpressure end of the working chamber 19,-a valve seat 48 arranged aroundthe inlet 46 at the rear' end of the valve chamber ii-and facing towardthe ,iow pressure end of the working chamber 19, a relief check valve 49arranged hi the valve chamber 45 and movable toward and from the seat 48therein, a supportingdisk -56 arranged the front partof the valvechamber and engaging with the inne'r'side of the front wall 12', and aspring 51 arranged in said valve cham her and bearing at its oppositeends the relief check valve 49 and the supporting isk 50" or othersupport.

The outlet 47 should be made comparatively small so as to retard thepassage of resistance liquid therethrough, the size of the outlet beingvaried to suit the desired capacity of the istrument. This orifice 467is so proportioned that at extremely high velocities it will operate asa choke to' retard the flow of resistance through the passage 45, 47independently of the retarding action of the valve 49, thereby obtainingwhat may be termed a modified viscous pressure control which the orificel? serves as a control valve; j

The spring 51 of this relief check valve device .is sufiiciently heavyso that when the instru l pressure end of the working chainmentis'subjected to normal loads this spring will hold the reliefcheck'valve 49 in itsclosed position and, when the piston 281s movingtoward the high pressure end of the working chamber 20,

will confine the liquid resistance therein "and thereby cause the shockabsorber to offer a-com-f paratively high resistance or'shockabsorbingeffect to-the load which is imposed upon the instrument at this time.If, however,{an unusually 10 heavy load is placed upon the-instrument atthis time -'which is greater than that for'which' the instrument wasdesignedto' carry under normal conditions, then the excess pressurewhich is 'de 7 veloped in the high pressure end of the working chamber2G will ca'usethe relief check valve 49 to be automatically pushed awayfrom its seat 48 and open the relief passage 46, and 47 through thepartitionsection 22'whereby some of theresista'njce liquid is'fpermittedto pass from the high pressure end of the workingchjambe'r 20' into thelow pressure end of the working chambera 19. Excessive pressure in theshock absorber is 7 therefore relieved at this time so that the same isnot strained unduly and the pasengers are not subjected to anuncomfortable riding action.

Under a comparatively slow movement of the pistons, duringnormalweather, or such Imovement during warm weather, when theresistance v liquid; is thinned and the pressure within the in strumentwill not rise-'abovea fixed limit, the

valve 49 will lift or unseat only after the 'necessary pressure hasreached a sufliciently high point,- and if the velocity ofthe liquidpassing this valve at this time is sufiiciently high, this valve remainsopen and maintains a constant pressure in the high pressure end oftherespective working chamber during the high pressure stroke of thepistons.

Means are provided whereby the resistance liquid in'th'e workingchambers islreplenished as required and -means are-also providedfor-prventing the escapeof resistance liquid through the joints of thebody to theexterior of the valve while the same is under internal"pressure" which means are embodied in the features of the pres entimprovements and are constructed as folishin'g chamber through anopening in the top- "thereof which opening is normally iclosed by meansof a cap 53 which is secured to the upper end of the replenishingchamberbymeans' of driving screws'54, as best shown in Fig.3, or by any othersuitable or approved means.

,, On the front part of the periphery of thefront head 12 of the bodyisfo'rmedianannularrecuperating groove 55 which together with the adjacentpart of the bore of the peripheral wall forms-an annular recuperatingchannelwhich is adapted to receive any resistance liquid which maypossibly leak iorwardly'through the joint between the from head 20. andthe peripheral wall- 10 of the body whenthe instrument is'subrf jectedto internal pressure.v i

Betweenits front and rear ends the bore of the bearing i7 inwhichtheishaft 30 turns is pro,- vided with an annular. interceptinggroove 56which is adaptedto receive or intercept any re sistance liquid whichmaybe forced forwardly H v equalizing portspr passa es 68,, 69 which cthe opposite ends respectively of the working from the working chambersthrough the: joint between the cooperating surfaces of the oper- =ingthe latter against the seat 60. w

ating shaft and thebearing "'17 during the internalpressur'e'to whichthe instrum'entis sub- ,J'fi d. Any-resistance fluid which :may be in 9tercepted by the groove 56 isconducted-to the *recuperatinggroove 55'bymeans of a branch'pas sage '57 extending from the interce'pting'g'roov'e 56 to the recuperating "groove 55, as shown I Fig. 3. When theresistance liquid thusrecovered in the recuperating" groove is in(excess of the capacity of: this groove'an'd'the passages'connectingtherewith'fthen the excess'o'i "such liquid is conducted from: therecuperating groove by. "one or more passages 58 to'the replenishingchamber,

each'of whichpassages is arrangediin the rearpartof the 'peripheral-wall of the body' and ex;

tends from-theupper partof' the recuperating groove 55-to' the lowerpart of the replenishing chamber 52,-as-shown'in Figs;=1,2'and 4.

When additional resistance-liquid is required in the working chambersthis is supplied thereto by means of a'replenishingportor passage 59leading from the lower part 'of the recuperating groove 55 to thelowerpart of oneof the working. chambers, for example theyworkingchamber 19', v

I as shownin Figs. 1, i andl'which replenishing 10vportcontainsa'valve.seat-60jtacing towardithe respective workingchamber and is adaptedito b'e'-,,. engaged by a check valve 61 capableof .moving-.:1;

towardand from thisseat 60. When thework ing. chambers .require.'additionalresistance liquid this is automatically supplied thereto by;

the flow ofr'esistance liquid from the replenishi:

ing chamber-.52 thence through-the recuperating port 59 into the lowerend of the working chain.-

of bothlworkingchambers during the operation. of the instrument bymeans'of thecheck-valved by-pas's port in the upper partitionqsectionfllv and the relief portin the lowerpartition section 22.Whenthetre'quisite amount ofresistance; liquidvhasibeen supplieditotheworking cham-w bers the replenishing port t59' i"s-automatically closedbyathe pressure within the'workingchamu; 'berswhich act upon;the checkvalve'61 for clos- For the purpose ot-permitting any air: which frombecoming air-bound one "or more vent plugs 62Jare provided each; ofvz whichtis arrangedinan I opening. 63 in -the=1upper partgof the front wallmay bepresentinathe resistanceliquid:togescape, s I therefrom andthereby preventrthebinstrument 125i l2 of the body-.andis'provided-inits'upper side, with-La longitudinal'igroove forming a vent port- 64.leading fromTthe J'upper -part of one of the-Q working .ch'a'mbei s..votthe adjacent upper-mart} of' the recuperating; groovew55, .as showninq-Eigsi 5 1, 4"an'd'7.u1 Y

eats; ,t rldimiiead rz 'or-tui ,7 shock absorberipbodyywith the;peripheral [wall 1 thereof by';meansllofga screw joint, as shown inFigs. 3:ancl .4; this'm'ay be effected bymeans of Figs. '8' and 9,in-which case the; adjacent edges same.

in this" me tasis? we e chambers are both formed wholly within the hub'IOofthe operatingshaft- 30,.. as shown in Fig, 9 andtheinterceptinggroove 56 is connected with; the lower partzof therecuperatinggroove 55rby' means of a-brlanch passage: 1L instead of;being; connected directly with the upper part. thereof,

asshown in Fig; 3. In other respects this modified form of. myinvention; is. substantially the 7 same as that. shown in Figs. 1-7. I

I claim; as my invention:

1'. A- hydraulic shock absorber comprising a body having. av peripheral.wall, a rear head formed.

integrally with said wall, and a. front head connected=with said walland. provided. withia;

central bearing, the space. enclosed; by said wall and heads forming; atleast one work.-,

ing chamber which is; adapted. to contain a resistance liquid, a pistonoscillating in. said:

working; chamber, andanqoperating shaft journaled'insaid bearingandconnected with said piston, said, front; head. being provided withaperipheral groove: forming with the inner side of said wall an annularrecuperating; passage-.2145 branch passage. leading/from saidrecuperatingpassage-tothe bore, ofsaidbearing, andareturn: passageleading from the lower partof saidmecuperatingpassage tothe lowerpartoflsaid working:

chamber.

2. A hydraulic shock absorber comprising: a

body having a peripheral wall, a .rear-headformed integrally. with saidwall, and a front head connected with said wall and provided withacentral bearing, thespace enclosed by'said wall and headsforming atleast one working chamber WhlChflSI adapted to. contain aresistanceliquid', a. piston oscillating in said working chamber, and.an operating shaft journaledin said bearing-andconv nected with saidpiston, said wallbeing provided on its upper side with a liquidreplenishing chamberyand said-front head having a recuperatingpassageonits periphery which is connected by a branch passagewith saidreplenishing chamber, by another branch passage withthe bore of said:bearing and by a check valved replenishing pas-f" sage withsaidworkingchamber.

3. A hydraulic shock absorber comprising av body having a peripheral.wall, a rear head formed I integrally with said wall, and a front head:con...

nected withisaidvwall and provided with a central bearing; the spaceenclosed by'said wall and. heads Y forming at least one'working.chamber'which is adapted to contain a resistance liquid; a piston os'-.'

cillatingin saidworking chamber; and'an oper-'.

ing passage with the lower part'of 'saidworking chamber.

4. A hydraulic shock absorber comprising a body having a peripheralwall, a rear head, and

a front head provided with'a'central' bearing, the space betweensaidwall and heads being divided by "diametrically opposite partitionsec-J 'tions into two working chambers which are adapted to containresistance liquid, each of saidi' .working chambers having high and lowpressure ends and .each partition section being arranged between thehighpressure end of one working lchamberyand; the low pressure end of theother working chamber, pistonsoscillatinginsaid work: ing. chambers,anoperating shaft. journaled in said bearing: and connectedwith saidpistons, a. by-passport arranged. in one of said, partition. sectionsand, connecting. the high andv low pressure ends of; the workingchambers on opposite sides ofQthe same and having a. valve seat facing,

toward the-respective high. pressure endfof. the" respectiveworking.chamber, a check valve. ar-

' ranged insaid by-passportaridadaptedte engage the seat thereinduring.high., pressure strokes of said pistons, a, relief port arrangedinthe other partitionandconnecting the. high and lowpressure. ends ofthe working c hambers on opposite sidesof the. same'and having. avalveseat facing toward the respective low pressure end of therespective-working chamber, a relief valve ar ranged in-said reliefchamber, an'da spring arranged in said relief chamber and operating on.said relief valve-for holding thesame yieldingly in, engagementwith theseatin therelief port.

5. A hydraulic shock absorber comprising a;

body having a peripheralwall, a rear head, and,

a front head provided with'a. central bearing, thespace between saidwall and heads being divided by diametrically; oppositepartitionsections" into two workingchambers which are adapted to containresistance liquid, each of said workingcham bers having, high and lowpressure ends and each partition section being arranged between thehighpressure end ofone workingchamber and the. low a pressure end of; theother working chamber, pisj tons oscillating in .said workingchambers,an operating shaft journaled in said bearing and connected with saidpistons; a by-pass. port armeeting the high and {low pressure ends ofthe- 11 0: ranged in. one of-said partition; sections and con workingchambers on opposite sidesof thesame and having a valveseat facingtowardthe respective high pressure end of, the respective working chamber, acheck valve arranged in said by -pass port andadaptedto engage theseattherein during high pressurerstrokes of: said pistons, arelief .portformed inythe other partition-section and consisting of a valve chamberhaving a valve seat at its inner end and havingits outer end extendv ingto an edge of said partition section which. is opposite the innerside ofone of said heads, and said-valve chamber having an inlet atone end.which leadsto the high pressure end of one ofsaid working chambers andan. outlet at its other.

end leading to the-low pressure'end of the other "working chamber, a'relief valve arranged in saidrelief y alvepchamber, a bearing diskarranged in said relief valve chamber and engaging the adjacent head ofthe body, and aspring, arranged in said relief valve chamber, betweensaidrelie'fvalve andbearing disk and operating to holdsaidrelief valveshut during normal loads onthe shock ab-- sorber-but to permitsaidrelief valve to open during abnormally high loads on theshockabsorber and allow" resistance liquid to pass through the reliefportfrorn the high pressure end of one working chamber to-the lowpressure end of the other working chamber atsuch times,

6; A hydraulic shockfabsorber:comprising a per ripheral wall having "arear. head, and having. a front head connected by: ajoint :with saidwall,v the space enclosed by said wall and heads forming a workingchamber adapted to .contain a resistance liquid, a piston operatinginrsaid' working chamber, there being a peripheralrecuperating. channelbetween said peripheral walland fronthead, said channel being exposed tothe joint be tween said front head and wall to intercept any" Ving'pressure stroke of said piston, a passage for conducting fluid fromsaid recuperating channel back to the working chamber, and a check valve,in said passage for checking flow of fluid from said working chamber tosaid recuperating channel. 7. A hydraulic shock absorber comprising abody having a peripheral wall, a permanent rear head, i

recuperating channel between said peripheral wall and said front head,said channel being exposed liquid escaping through said joint connectiondurto the joint between said front head andwall-to intercept any liquid,escaping though said joint connection during pressure stroke of saidpiston,-

a replenishing chamber formed in said body above said working chamber, apassage connecting said replenishing chamber withlthe top of saidrecuperating channel, and a second passage connecting the bottom of saidrecuperating, channel with said 1 working chamber whereby fluid may flowfrom said replenishing chamber into said working chamber, and acheckvalve in said second passage for preventing flow of fluid from saidworking chamber to said recuperating channeL,

RALPH F. PEO.

